Lipid and lipid carbon stable isotope composition of the hydrothermal vent shrimp Mirocaris fortunata: evidence for nutritional dependence on photosynthetically fixed carbon

Mirocaris fortunata were sampled from the Lucky Strike hydrothermal vent area (Eiffel Tower site) on the mid-Atlantic ridge during the French DIVA 2 cruise (June 1994). Small adults (17 to 22 mm total length), although morphologically identical, could be divided into 2 categories on the basis of pigmentation, lipid composition and C-13/C-12 stable isotope ratios of fatty acids. Highly pigmented small adults (8.6 to 9.2 mu g carotenoid shrimp(-1)) contained higher levels of total lipid than similar-sized individuals containing lower levels of pigment (0.9 to 2.9 mu g carotenoid shrimp(-1)). Lipid class analysis indicated that wax esters comprised 62.5% of total lipid in the former group. These pigmented shrimp also contained high proportions of polyunsaturated fatty acids (PUFA), particularly the phototrophic microplanktonic markers 20:5(n-3) and 22:6(n-3) (14.0 and 33.5% respectively). By contrast small adults (22 mm) and adult shrimp (25 to 26 mm) with low levels of carotenoid pigmentation contained lower amounts of total lipid, little or no wax ester and low levels of 20:5(n-3) and 22:6(n-3), but did contain 16:2(n-4) and 18:2(n-4) and the non-methylene interrupted dienes 20:2 Delta 5,13 and 22:2 Delta 7,15. GC-IRMS analysis of all fatty acids and fatty alcohols in the pigmented small adults indicated delta(13)C values of -18.2 to -27.7 parts per thousand, which is consistent with a photosynthetic carbon source for these compounds. The C-13/C-12 isotope composition of fatty acids from low-pigmented small adults and adults was more variable (-12.5 to -33.1 parts per thousand) and suggests a bimodal distribution which may be attributable to differing nutritional sources or the physiological/reproductive status of these shrimp. Samples of eggs, which are carried by the female on the pleopods, represented approximately 57% of total somatic lipid which indicates a substantial reproductive investment by this species. The egg lipids comprised high proportions of triacylglycerols (64.4 to 78.0% of total lipid) whilst the fatty acid composition was dominated by the monounsaturated fatty acids 16:1(n-7), 18:1(n-7) and 18:1(n-9), which accounted for 65.7 to 33.5% of total fatty acids. By contrast, PUFA were relatively minor components of egg lipids, particularly 20:5(n-3) and 22:6(n-3), which accounted for only 1.1 and 2.9% of total egg fatty acids respectively. This indicates that the reproductive investment by this species is supported mainly by material derived from bacterial chemosynthesis. The potential for M. fortunata hedge betting by producing larvae which either metamorphose at the vent site or adopt a bathypelagic lifestyle and delay metamorphosis to facilitate more widespread dispersal is discussed.

Micoencapsulation of bioactive plant extracts: a tool to functionalize cottage cheeses

Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are two examples of plants with reported antioxidant and antimicrobial properties, which can be related with their composition in phenolic compounds [1,2]. Furthermore, according to previous results of our research group, the direct incorporation of the aqueous extracts showed capacity to maintain the nutritional properties of the cottage cheeses, up to 7 days of storage, while improving the antioxidant potential. However, after 14 days, a decrease in the antioxidant properties was observed [1,2], which can be related with factors such as light, moisture, temperature and pH, that can cause bioactive compounds degradation. Therefore, the aim of the present study was to prepare microcapsules with the aqueous extracts of fennel and chamomile for incorporation in cottage cheese samples, in order to protect the bioactive molecules present in the extracts, such as phenolic compounds, and prevent the decrease of the antioxidant activity observed after the 14 days period. The microspheres were prepared using an atomization/coagulation technique. Sodium alginate was used as the matrix material to produce the microspheres that were characterized through optical microscopy (OM), during and after atomization, for inspecting morphology. The encapsulation efficiency (EE) was determined by HPLC-DAD by an indirect method by analysing the coagulation solution. FTIR was also used to attest the presence of the extract inside of the alginate matrix. These microencapsulated extracts were incorporated in cottage cheese samples that were further characterized in terms of nutritional properties and antioxidant potential right after incorporation, and after 7 and 14 days of storage at 4•c. The EE was estimated as -100% and the FTIR analysis confirmed the presence of the extracts inside the microspheres. The results showed that the incorporation of the microencapsulated extracts did not cause changes in the nutritional value of cottage cheeses (through a comparison with control samples without extracts). The predominant fatty acids were palmitic (C16:0) and oleic (CI8:0) acids. The order of abundance of fatty acids was as follows: saturated fatty acids (SF A)> monounsaturatcd fatty acids (MUF A)> polyunsaturated fatty acids (PUF A). Regarding free sugars, lactose was the only sugar identified and quantified in all samples. Regarding the antioxidant activity, the samples functionalized with the microencapsulated extracts showed a higher preservation of this property even after the 7th day of storage. Overall, the incorporation of the protected plant extracts in dairy foods can be a strategy to provide health benefits to consumers.

Nutritional and chemical characterization of food products enriched with biological produced fruits of Vaccinum myrtillus L

Vaccinum myrtillus L. belongs to Ericaceae family, being commonly known for its sweet small fruits: the blueberries. Widely consumed in fresh, these fruits are also used in jams and marmalades due to their digestive and hypoglycemic properties and also due to the presence of several bioactive compounds [!]. Therefore, it has become a very appealing matrix in the development of functional products that, beyond their nutritional properties, will add a long-term beneficial physiological/health effect [2]. In the present work, three novel blueberry based products developed by RBR Foods Company (Portugal), were characterized in terms of their nutritional and chemical properties: carbohydrates, ash, proteins, fat and energetic value (following official methods of food analysis), fatty acids profile (by CG-FID), soluble sugars (by HPLCRI), organic acids (by HPLC-DAD) and tocopherols (by HPLC-fluorescence). The products result from a mixture of the fruits with rose petals (PI), marigold petals (P2) and apple and goji berries (P3). The blueberry fruits were used as control sample. The nutritional profile of the novel products was very similar to the control sample: the carbohydrates were the most abundant macronutrient, followed by proteins and total fat. Regarding sugars, fructose, glucose and sucrose were identified in all the samples. P 1 and P2 didn't show significant differences in comparison to the control, however, P3 revealed a lower concentration of sugars. In terms of fatty acids composition, all the studied samples presented higher contents in polyunsaturated fatty acids, especially due to the contribution of linoleic and alinolenic acids. The results of tocopherols revealed that the control sample only presented two isoforrns of tocopherols, a- and y-tocopherol, being the same observed in P3. However, P 1 revealed the presence of all the isoforrns of tocopherols, while P2 was lacking otocopherol; which is related with the contribution of rose and marigold petals, respectively. The a-tocopherol isoforrn was the most abundant in all the studied samples. Overall, this work contributed to the nutritional characterization of novel blueberry based products and is a part of a wider project that aims the detailed study of these products, namely their potential to be used as functional foods.

The use of wild fruits of Fragaria vesca L. in preparations with bioactive properties: chemical characterization, antioxidant, antibacterial and antibiofilm activities

Wild strawberry, Fragaria vesca L., belongs to Rosaceae family and is commonly found in roadsides and slopes [1]. The most consumed parts of this plant are its sweet small fruits, which constitute a source of vitamins and phenolic compounds, being also used in infusions due to their organoleptic properties and for the treatment of some intestinal disorders [2, 3]. In the present work, F. vesca fruits were evaluated for their nutritional value and further used in the preparation of infusions. The chemical composition of the fruits and corresponding infusions was determined in terms of soluble sugars, organic acids, tocopherols, folates (by HPLC coupled to different detectors), phenolic compounds (by HPLC-DAD/ESI-MS) and mineral elements (atomic absorption spectroscopy). Some of these bioactive compounds were correlated with antioxidant and antibacterial properties evaluated either in infusions as also in hydromethanolic extracts. Carbohydrates were the main macronutrients in the fruits, followed by fat and proteins. Regarding the fatty acids, polyunsaturated fatty acids showed higher prevalence, mainly due to the presence of D-linolenic (Cl8:3n3) and y-linolenic (Cl8:3n6) acids. Sucrose and citric acid were, respectively, the main sugar and organic acid found in the fruits and in its infusions. The microelement found in higher amounts in both samples was manganese, while potassium and calcium were the macroelements present in higher levels in the fruits and infusions, respectively. Both samples presented folates and tocopherols, being ytocopherol the main isoform detected in the fruits, while a-tocopherol was the only isoform quantified in the infusion. The hydromethanolic extract prepared from the fruits gave higher antioxidant and antibacterial activities, namely against Escherichia coli and Pseudomonas aeruginosa, than the infusion; it also showed capacity to inhibit the formation of bacterial biofilm. Both bioactivities are highly correlated with the presence of phenolic compounds, in which the major are ellagic acid derivatives (sanguiin hlO) followed by tlavan 3-ols ((+)catechin) and anthocyanin compounds (pelargonidin-3-glucoside). Although fruits of wild F. vesca are mainly consumed in fresh, this study also proves the potentiality of their infusions as a source of bioactive molecules and properties.

Effets préventifs et thérapeutiques des polyphénols dans un modèle in vitro et in vivo de maladie inflammatoire de l’intestin : caractérisation des polyphénols de la pelure de pomme et de la canneberge par spectrométrie de masse

La muqueuse intestinale est exposée à des agents oxydants provenant de l’ingestion d’aliments modifiés, de cellules immuno-inflammatoires et de la flore intestinale. Une diète élevée en fruits et légumes peut diminuer le stress oxydant (SOx) ainsi que l’inflammation via plusieurs mécanismes. Ces effets bénéfiques peuvent être attribuables à leur contenu élevé en polyphénols. La première étude de mon doctorat consistait à tester l’hypothèse que les polyphénols extraits de pelures de pomme (DAPP) pouvaient diminuer le stress oxydant et l'inflammation impliqués dans les maladies inflammatoires de l'intestin (MII). Nous avons caractérisé les polyphénols des DAPP par spectrométrie de masse (LC-MS) et examiné leur potentiel antioxydant et anti-inflammatoire au niveau des cellules intestinales. L’identification des structures chimiques des polyphénols a été effectuée par LC-MS. Le SOx a été induit par l’ajout du complexe fer/ascorbate (Fe/Asc, 200 µM/2 mM) et l’inflammation par la lipopolysaccharide (LPS, 200µg/mL) à des cellules intestinales Caco-2/15 pré-incubées avec les DAPP (250 µg/mL). L’effet du SOx est déterminé par le dosage du malondialdéhyde (MDA), de la composition des acides gras polyinsaturés et de l’activité des enzymes antioxydantes endogènes (SOD et GPx). L’impact des DAPP sur l’inflammation a été testé par l’analyse de l’expression des marqueurs inflammatoires: cyclooxygénase-2 (COX-2), le facteur de nécrose tumorale alpha (TNF-a et l’interleukine-6 (IL-6) et les facteurs de transcription NF-KB, Nrf-2 et PGC1α par immunobuvardage. Nos données ont montré que les flavonols et les flavan-3-ols constituent les composés polyphénoliques majoritaires des DAPP. L’ajout de Fer2+/Asc a provoqué une augmentation de la peroxidation lipidique comparativement aux cellules contrôles, un appauvrissement des acides gras polyinsaturés n-3 et n-6, et une modulation des enzymes antioxydantes, se traduisant par une augmentation de l’activité de la SOD et une diminution de la GPx. En contrepartie, les DAPP ont exhibé leur potentiel à corriger la plupart des perturbations, y compris l’expression protéique anormalement élevée du COX-2 et la production de la prostaglandine E2 (PGE2), ainsi que l’inflammation telle que réflétée par les facteurs NF-κB, TNF-α et IL-6. Par ailleurs, les mécanismes sous-jacents à ces changements bénéfiques des DAPP ont fait intervenir les facteurs de transcription antioxydants (Nrf-2, PGC1α). Vraisemblablement, cette première étude a permis de démontrer la capacité des DAPP à amoindrir le SOx et à réduire l’inflammation, deux processus étroitement impliqués dans les MII. Dans la deuxième étape de mon doctorat, nous avons voulu comparer les résultats de DAPP à ceux des polyphénols dérivant de la canneberge qui est considérée par la communauté scientifique comme le fruit ayant le plus fort potentiel antioxydant. À cette fin, nous avons caractérisé l’effet des composés polyphénoliques de la canneberge (CPC) sur le SOx, la défense antioxydante et l’inflammation au niveau intestinal tout en définissant leur métabolisme intraluminal. Les différents CPC ont été séparés selon leur poids moléculaire par chromatographie et leurs structures chimiques ont été identifiées par LC-MS. Suite à une pré-incubation des cellules Caco-2/15 avec les extraits CPC (250 µg/mL), le Fe/Asc et la LPS ont été administrés comme inducteurs du SOx et de l’inflammation, respectivement. La caractérisation globale des CPC a révélé que les acides phénoliques composaient majoritairement l’extrait de canneberge de petit poids moléculaire (LC) alors que les flavonoïdes et les procyanidines dimériques/trimériques représentaient l’extrait de poids moléculaire moyen (MC) tout en laissant les procyanidines oligo et polymériques à l’extrait de haut poids moléculaire (HC). Les CPC ont permis de restaurer la plupart des perturbations engendrées dans les Caco-2/15 par le Fe/Asc et le LPS. Les CPC exhibaient le potentiel d’abaisser les niveaux de MDA, de corriger la composition des acides gras polyinsaturés n-3 et n-6, d’augmenter l’activité des enzymes antioxydantes (SOD, GPx et CAT) et d’élever l’expression de Nrf2 et PGC1α. En outre, les CPC pouvaient aussi réduire les niveaux élevés des protéines inflammatoires COX-2, TNF-α et IL-6 ainsi que la production des PGE2 par un mécanisme impliquant le NF-κB. Au niveau mitochondrial, les procyanidines oligomériques ont réussi à corriger les dysfonctions reliées à la production d’énergie (ATP), l’apoptose (Bcl-2, Cyt C et AIF) et le statut des facteurs de transcription mitochondriaux (mtTFA, mtTFB1, mtTFB2). Dans le but de bien comprendre les mécanismes d’action des CPC, nous avons défini par LC-MS les composés polyphénoliques qui ont été transportés ou absorbés par l’entérocyte. Nos analyses soulignent le transport (i) des acides cinnamiques et benzoïques (LC); (ii) la quercétine glycosylée et conjuguée et les procyanidines dimériques de type A (MC); et (iii) l’épicatéchine et les procyanidines oligomériques (HC). Les processus de métabolisation (méthylation, glucuronidation et sulfatation) au niveau de l’entérocyte ont probablement permis le transport de ces CPC surtout sous leur forme conjuguée. Les procyanidines oligomériques ayant un degré de polymérisation supérieur à 2 (HC) ont semblé adhérer aux cellules Caco-2/15. L’épicatéchine suivi par les procyanidines dimériques de type A ont été trouvés majoritaires au niveau des mitochondries. Même si nous ignorons encore l’action biologique de chaque composé polyphénolique, nous pouvons suggérer que leurs effets combinatoires exercent des fonctions antioxydantes, anti-inflammatoires et mitochondriales dans le modèle intestinal Caco-2/15. Dans une troisième étape, nous avons procédé à l’évaluation des aspects préventifs et thérapeutique des DAPP tout en sondant les mécanismes sous-jacents dans une étude préclinique. À cette fin, nous avons exploité le modèle de souris avec colite expérimentale provoquée par le Dextran Sulfate de Sodium (DSS). L’induction de l’inflammation intestinale chez la souris C57BL6 a été effectuée par l’administration orale de DSS à 2.5% pendant 10 jours. Des doses physiologiques et supra-physiologiques de DAPP (200 et 400 mg/kg/j, respectivement) ont été administrées par gavage pendant 10 jours pré- et post-DSS. L’inflammation par le DSS a provoqué une perte de poids, un raccourcissement du côlon, le décollement dystrophique de l’épithélium, l’exulcération et les infiltrations de cellules mono et polynucléaires au niveau du côlon. De plus, le DSS a induit une augmentation de la peroxidation lipidique, une régulation à la baisse des enzymes antioxydantes, une expression protéique à la hausse de la myéloperoxidase (MPO), du COX-2 et de la production des PGE2. Par ailleurs, les DAPP ont permis de corriger ou du moins d’alléger la plupart de ces anomalies en situation préventive ou thérapeutique, en plus d’abaisser l’expression protéique de NF-κB et des cytokines inflammatoires (TNF-a et l’IL-6) tout en stimulant les facteurs de transcription antioxydants (Nrf-2, PGC1α). Conséquemment, les polyphénols des DAPP ont exhibé leur puissant pouvoir antioxydant et anti-inflammatoire au niveau intestinal dans un modèle in vivo. Leurs actions sont associées à la régulation des voies de signalisation cellulaire et des changements dans la composition du microbiote. Ces trois projets de recherche permettent d’envisager l’évaluation des effets préventifs et thérapeutiques des DAPP cliniquement chez les patients avec des désordres inflammatoires de l’intestin.

Le rôle des acides gras oméga-3 sur la balance énergétique, la régulation de l’appétit, l’état émotionnel et l’implication du récepteur GPR120

L’obésité est un facteur de risque lié à des problèmes physiques, émotionnels et comportementaux. Aujourd’hui, l’alimentation est composée d’un régime typiquement occidental «Western diet» qui est riche en acides gras saturés (AGS) et pauvre en acides gras polyinsaturés (AGPI) tel que les oméga-3 (N-3) et occasionnant un déséquilibre du ratio alimentaire N-6/N-3. Ce déséquilibre est une des causes de la prévalence des maladies mentales y compris celles des troubles de l'humeur et de l’anxiété. L’acide docosahexaénoïque (ADH, 22: 6 n-3) est l’acide gras (AG) le plus abondant dans le cerveau et son accumulation est particulièrement élevée pendant la période périnatale. Il joue un rôle important dans le développement neuronal et d'autres fonctions du cerveau tel l'apprentissage et la mémoire. Des perturbations de l’environnement périnatal peuvent influencer à très long terme l’avenir de la descendance en la rendant plus susceptible de développer des problèmes d’obésité dans un contexte nutritionnel riche. On ignore cependant si le déficit alimentaire chez la mère et particulièrement en ADH aura un impact sur la motivation alimentaire de la progéniture. L’objectif principal de cette thèse est d’étudier le rôle potentiel des N-3 sur la balance énergétique, la motivation alimentaire, la dépression et le niveau d’anxiété des descendants de souris mâles adultes assujetties à une alimentation riche en gras. Nos données ont démontré qu‘un régime maternel déficitaire en ADH durant la période périnatale incitait la descendance à fournir plus d’effort afin d’obtenir un aliment palatable. Ceci entraînerait un dérèglement de l’homéostasie énergétique en augmentant le gain de poids et en diminuant l’activité locomotrice tout en exacerbant le comportement de type anxieux dès que les souris sont exposées à un milieu obésogène. Les acides gras libres (AGL) sont des nutriments essentiels fonctionnant comme des molécules de signalisation dans le cerveau en ayant des récepteurs qui jouent un rôle important dans le contrôle du métabolisme énergétique. Parmi eux, on distingue un récepteur couplé à la protéine G (GPCR), le GPR120. Ce récepteur activé par les AGPI ω-3 intervient dans les mécanismes anti-inflammatoires et insulino-résistants via les N-3. Une mutation dans le gène GPR120 occasionnée par une réduction de l’activité de signalisation du gène est liée à l’obésité humaine. L'objectif premier de cette deuxième étude était d’évaluer l'impact de la stimulation pharmacologique de GPR120 dans le système nerveux central (SNC) sur l'alimentation, les dépenses d'énergie, le comportement de type anxieux et la récompense alimentaire. Nos résultats démontrent qu’une injection centrale aiguë d'agoniste GPR120 III réduit la prise alimentaire ad libitum et la motivation alimentaire pour un aliment riche en gras et en sucre; ainsi que les comportements de type anxieux. L’injection centrale chronique (21 jours) de ce même agoniste GPR120 III transmis par une pompe osmotique a démontré que les souris placées sous diète hypercalorique (HFD n’ont présenté aucune modification lors de la prise alimentaire ni de gain de poids mais qu’il y avait comparativement au groupe de véhicule, une réduction du comportement de type anxieux, que ce soit dans le labyrinthe en croix surélevé (LCS) ou dans le test à champ ouvert (OFT). L’ADH est reconnu pour ses propriétés anorexigènes au niveau central. De plus, la stimulation des récepteurs de GPR120 au niveau du cerveau avec un agoniste synthétique peut produire un effet intense intervenir sur le comportement lié à l'alimentation des rongeurs. Trouver une approche visant à contrôler à la fois la neuroinflammation, la récompense alimentaire et les troubles émotionnels aiderait assurément au traitement de l'obésité et du diabète de type 2.

Chromatographic techniques to obtain the biomolecules profile of wild Suillus granulates

In recent years the interest in naturally occurring compounds has been increasing worldwide. Indeed, many of the bioactive compounds currently used as medicines have been synthesized based on the structure of natural compounds [1]. In order to obtain bioactive fractions and subsequently isolated compounds derived from natural matrices, several procedures have been carried out. One of these is to separate and assess the concentration of the active compound(s) present in the samples, a step in which the chromatographic techniques stand out [2]. In the present work the mushroom Sui/Ius granulatus (L.) Roussel was chemically characterized by chromatographic techniques coupled to different detectors, in order to evaluate the presence of nutritional and/or bioactive molecules. Some hydrophilic compounds, namely free sugars, were identified by high performance liquid chromatography coupled to a refraction index detector (HPLC-RI), and organic and phenolic acids were assessed by HPLC coupled to a photodiode array detector (HPLC-PDA). Regarding lipophilic compounds, fatty acids weredetermined by gas chromatography with a flame ionization detector (GC-FID) and tocopherols by HPLC-fluorescence detection. Mannitol and trehalose were the main free sugars detected. Different organic acids were also identified (i.e. oxalic, quinic and fumaric acids), as well as phenolic acids (i.e. gallic and p-hydroxybenzoic acids) and the related compound cinnamic acid. Mono- and polyunsaturated fatty acids were the prevailing fatty acids and a-, ~- and ~-tocopherol were the isoforms of vitamin E detected in the samples. Since this species proved to be a source of biologically active compounds, the antioxidant and antimicrobial properties were evaluated. The antioxidant activity was measured through the reducing power, free radical's scavenging activity and lipid peroxidation inhibition of its methanolic extract, and the antimicrobial activity was also tested in Gram positive and Gram negative bacteria and iri different fungi. S. granulatus presented antioxidant properties in all the performed assays, and proved to inhibit the growth of different bacterial and fungal strains. This study is a first step for classifying S. granulatus as a functional food, highlighting the potential of mushrooms as a source of nutraceutical and biologically active compounds.

Bioactivity and chromatographic analysis of nutrients and non-nutrients of two Leccinum species

Nowadays the rising cost of health care and pharmaceutical products, the increase in life expectancy as well as the demand for an improved quality of life, has led to an increased concern about food intake and an emergence of new concepts of nutrition [1]. Mushrooms have been pointed out as an excellent option to include in a healthy diet, due to their nutritional value [2] associated with their bioactive properties [3]. The current study presents the chemical profile of two edible species, Leccinum molle (Ban) Ban and Leccinum vulpinum Watling, harvested in the outskirts of Bragan9a (Northeastern Portugal), regarding their content in nutrients and nonnutrients. Individual profiles of sugars and fatty acids were obtained by HPLC-RI and GC-FID, respectively. Tocopherols were analysed by HPLC-fluorescence, and the non-nutrients (i.e., phenolic and other organic acids) by HPLC-PDA. The antioxidant activity of the methanolic extracts obtained from both species was assessed with different assays (e.g. reducing power, radical scavenging activity and lipid peroxidation inhibition) and their hepatotoxicity was evaluated in primary cell cultures obtained from porcine liver, PLP2. Generally, both Leccinum species revealed similar nutrient profiles, with low fat levels, fructose, mannitol and trehalose as the foremost free sugars, and higher percentages of mono- and polyunsaturated fatty acids in comparison with saturated fatty acids. The presence of bioactive compounds was also detected, namely phenolic (e.g., gallic, protocatechuic and p-hydroxybenzoic acids) and organic acids (e.g., citric and fumaric acids). Both species presented antioxidant properties, being L. vulpinum the species which showed the most promising results (higher contents of total phenolic acids and lower ECso values in all the performed assays). Neither of the extracts presented toxicity against the liver primary cells PLP2, up to maximal concentration tested (Giso > 400 μg/ml).

Sources de variation intra-populationelle de la morphologie des otolithes: asymétrie directionnelle et régime alimentaire

Otoliths are calcified structures located in Osteichthyes’ inner ear that are involved in audition and balance. Their morphology is used as an indicator of various ecological processes or properties. This application requires identifying the endogenous and exogenous factors that act simultaneously as sources of shape variation. This thesis aims at detecting and quantifying the relative contributions of directional asymmetry and diet to otolith shape variation at the intra-population level. Directional asymmetry between left and right otoliths was found in flat-fishes, the blind-side otolith being always longer and larger, whereas it was negligible in round-fishes. However, asymmetry amplitude never exceeded 18 %, which suggests evolutionary canalization of otolith shape symmetry. A correlation between global diet and otolith was detected in 4 species studied in situ. Diet composition contributed more than food amount to morphological variation and affected otolith shape both globally and locally. An experimental study on sea bass (Dicentrarchus larbrax) showed that diet composition in terms of essential polyunsaturated fatty acids at larval stage affects otolith morphogenesis during juvenile stage without impacting on individuals’ somatic growth. This result suggests a direct effect of diet on otolith shape and not an indirect one through the somatic-otolith growth relationship. This effect disappeared at later stages, morphogenetic trajectories converging back to a similar shape, which suggests ontogenetic canalization of otolith shape.

Nutritional and biochemical profiling of Leucopaxillus candidus (Bres.) singer wild mushroom

The wild mushroom Leucopaxillus candidus (Bres.) Singer was studied for the first time to obtain information about its chemical composition, nutritional value and bioactivity. Free sugars, fatty acids, tocopherols, organic and phenolic acids were analysed by chromatographic techniques coupled to different detectors. L. candidus methanolic extract was tested regarding antioxidant potential (reducing power, radical scavenging activity and lipid peroxidation inhibition). L. candidus was shown to be an interesting species in terms of nutritional value, with high content in proteins and carbohydrates, but low fat levels, with the prevalence of polyunsaturated fatty acids. Mannitol was the most abundant free sugar and β-tocopherol was the main tocopherol isoform. Other compounds detected were oxalic and fumaric acids, p-hydroxybenzoic and cinnamic acids. The methanolic extract revealed antioxidant activity and did not show hepatoxicity in porcine liver primary cells. The present study provides new information about L. candidus.

Leccinum molle (Bon) Bon and Leccinum vulpinum Watling: The First Study of Their Nutritional and Antioxidant Potential

This work presents the chemical profile of two edible species of mushrooms from the genus Leccinum: Leccinum molle (Bon) Bon and Leccinum vulpinum Watling, both harvested on the outskirts of Bragança (Northeastern Portugal). Both species were prepared and characterized regarding their content in nutrients (i.e., free sugars, fatty acids and vitamins), non-nutrients (i.e., phenolic and other organic acids) and antioxidant activity. To the best of our knowledge, no previous studies on the chemical characterization and bioactivity of these species have been undertaken. Accordingly, this study intends to increase the available information concerning edible mushroom species, as well as to highlight another important factor regarding the conservation of the mycological resources--their potential as sources of nutraceutical/pharmaceutical compounds. Overall, both species revealed similar nutrient profiles, with low fat levels, fructose, mannitol and trehalose as the foremost free sugars, and high percentages of mono- and polyunsaturated fatty acids. They also revealed the presence of bioactive compounds, namely phenolic (e.g., gallic acid, protocatechuic acid and p-hydroxybenzoic acid) and organic acids (e.g., citric and fumaric acids) and presented antioxidant properties.

Suitability of gamma irradiation for preserving fresh-cut watercress quality during cold storage

The suitability of gamma irradiation (1, 2 and 5kGy) for preserving quality parameters of fresh-cut watercress (Nasturtium officinale R. Br.) during storage at 4±1°C for 7d was investigated. The storage time decreased the protein content and the main carbohydrates, and increased the levels of malic and fumaric acids, sucrose and mono- and polyunsaturated fatty acids (MUFA and PUFA). The different irradiation doses did not caused any significant colour change. In general, the 2kGy dose favoured PUFA and was the most suitable to preserve the overall postharvest quality of fresh-cut watercress during cold storage. In turn, the 5kGy dose better preserved the antioxidant activity and total flavonoids and favoured MUFA, tocopherols and total phenolics, thus originating a final product with enhanced functional properties. Therefore, the suitability of gamma irradiation for preserving fresh-cut watercress quality during cold storage was demonstrated.

Non-fermented and fermented jabuticaba (Myrciaria cauliflora Mart.) pomaces as valuable sources of functional ingredients

abuticaba (Myrciaria cauliflora. Mart) is a highly perishable fruit native to Brazil, which is consumed both fresh and industrially processed in the form of juices, jams, wines and distilled liqueurs. This processing generates a large amount of waste by-products, which represent approximately 50% of the fruit weight. The by-products are of interest for obtaining valuable bioactive compounds that could be used as nutraceuticals or functional ingredients. In this study, fermented and non-fermented jabuticaba pomaces were studied regarding their hydrophilic and lipophilic compounds, as well as their antioxidant properties, including: soluble sugars, organic acids and tocopherols (using high performance liquid chromatography coupled to refraction index, diode array and fluorescence detector, respectively); phenolics and anthocyanins, (using liquid chromatography coupled to diode array detection, and mass spectrometry with electrospray ionization); and fatty acids (using gas-liquid chromatography with flame ionization detection). The analytical data demonstrated that jabuticaba pomaces are a rich source of bioactive compounds such as tocopherols, polyunsaturated fatty acids and phenolic compounds (namely hydrolyzable tannins and anthocyanins) with antioxidant potential. Therefore, jabuticaba pomace may have good potential as a functional ingredient in the fabrication of human foods and animal feed.

Estudio molecular en dos hermanas afectadas por ictiosis congénita autosómica recesiva : descripción de una nueva mutación causal en TGM1

Se describe la variante homocigota c.320-2A>G de TGM1 en dos hermanas con ictiosis congénita autosómica recesiva. El clonaje de los transcritos generados por esta variante permitió identificar tres mecanismos moleculares de splicing alternativos.

RELAZIONE TRA IL CONSUMO DI OLIO EXTRAVERGINE DI OLIVA E I CASI DI DECESSO PER MALATTIA DI ALZHEIMER IN SPAGNA

In the chemical composition of olive oil (Olea europaea L.) it is emphasized the massive presence of oleic acid (over 70%), monounsaturated fatty acid part of the family of omega 9, a 7-8% linoleic acid (omega 6) and a small presence (0.5-1%) of linolenic acid (omega 3). For its high content of monounsaturated fatty acids, olive oil is the most stable and therefore the most suitable for heating, compared to oils with a dominance of polyunsaturated fatty acids. Interest in vitamin E has increased in recent years, thanks to its high antioxidant power and its role against related diseases with age-related, visual, dermatological, cardiovascular disorders Alzheimer’s disease and more. Vegetable oils are a major source of vitamin E through diet (Sayago et al., 2007), especially with the variety of olives “Hojiblanca”. Thanks to unsaturated fatty acids cell oxidation can be prevented: this helps prevent many illness, and even premature aging. So far, the advantages acknowledged to olive oil are those of lowering cholesterol, preventing cardiovascular disease, diabetes and cancer. Among the most recent researches it is important to distinguish the studies carried out on their contribution to the prevention and treatment of breast cancer and Alzheimer’s disease. Researchers found that in addition to the benefi ts that give monounsaturated fats, in extra virgin olive oil, there is a substance called “oleocanthal”, which helps protect nerve cells damaged in Alzheimer’s disease. The importance of this discovery is enormous when one considers that only Alzheimer’s disease affects 30 million people around the world, with a different distribution depending on the type of oil in the diet (Olguín Cordero, 2012). The latest research endorses that oleocanthal works by destroying cancer cells without affecting the healthy ones, as it is stated in the Molecular and Cellular Oncology Journal. Studies carried out in different Spanish universities have concluded that thanks to the antioxidant power of olive oil, a disease such as Alzheimer can be prevented. In conclusion, we can say that the Mediterranean diet rich in extra virgin olive oil greatly infl uences on human health, reducing, delaying or even eliminating several diseases.